Abstract:

In view of the lifelong impact of Obstetrical Brachial Plexus Palsies (OBPP), prevention
of OBPP would be of great significance. Despite contemporary advances in antenatal
planning and assessment, OBPP remains an unfortunate consequence after difficult
childbirth. Permanent brachial plexus palsy is a leading cause of litigation related to birth
trauma.
Objectives: To determine the incidence of Obstetrical Brachial Plexus Palsy (OBPP),
Cephalopelvic Disproportion (CPD) and macrosomia in KwaZulu-Natal. As well as to
investigate the relationship between OBPP and CPD, and the relationship between OBPP
and macrosomia. The study also aimed to determine whether antenatal risk factors could
identify those prone to OBPP.
Study design: This was a case control study that included all deliveries from 1997 to
2000 from four provincial hospitals (Addington, King Edward VIII, Prince Mshiyeni
Memorial and RK Khan hospital). The outcome variable was OBPP. Results were
analyzed using Statistical Program for Social Sciences (SPSS).
Results: A total of 60 infants of 76 352 deliveries sustained OBPP. The incidence of
OBPP was found to be 0.72 per 1000 deliveries. The incidence of CPD was found to be
33.5 per 1000 deliveries and the incidence of macrosomia was found to be 16.7 per 1000
deliveries. Race, Maternal height> 150 cm, gravida >3, parity >4, history of a previous
big baby, normal vaginal delivery, delivery by a midwife, difficult labour, inadequate or
doubtful pelvic capacity, birth weight of >3700 g and gestation period> 34 weeks were
significant risk factors. Logistic regression analysis showed that race, parity> 4, normal
vaginal delivery and gestation period> 35 weeks were the variables most associated with
OBPP. Using linear regression model was obtained for the calculation of predictive risk
scores.
Conclusion: Using standard statistical formulae the probability of OBPP can be
calculated in women with significant risk factors from the logistic regression formula.
This would need to be validated and could provide a useful tool for screening for OBPP
thus contributing to preventing this devastating complication of birth trauma. The risk
assessment profile would contribute greatly to the prediction of OBPP and the subsequent
prevention of this debilitating birth injury.